Insulation Savings Calculator — Formula
## How to Calculate Insulation Savings
Insulation reduces heat transfer, lowering the energy needed for heating and cooling.
### Formula
**Efficiency Gain = 1 - (Current R-Value / New R-Value)**
**Annual Savings = HVAC Cost * Efficiency Gain**
### Recommended R-Values (US)
- Attic: R-38 to R-60
- Walls: R-13 to R-21
- Floors: R-25 to R-30
- Crawl space: R-25
Insulation reduces heat transfer, lowering the energy needed for heating and cooling.
### Formula
**Efficiency Gain = 1 - (Current R-Value / New R-Value)**
**Annual Savings = HVAC Cost * Efficiency Gain**
### Recommended R-Values (US)
- Attic: R-38 to R-60
- Walls: R-13 to R-21
- Floors: R-25 to R-30
- Crawl space: R-25
Esempio Risolto
Upgrade attic insulation from R-11 to R-38 with $2,000/year HVAC costs and $2,500 upgrade cost.
- Efficiency gain: 1 - 11/38 = 1 - 0.289 = 71.1%
- Annual savings: $2,000 * 0.711 = $1,421
- Payback: $2,500 / $1,421 = 1.8 years
- 10-year net savings: $1,421 * 10 - $2,500 = $11,710